Electrical devices can be deployed in a well (used for producing hydrocarbons from a reservoir or for injecting fluids into a reservoir) to perform various downhole tasks, such as well logging, flow control, and so forth. Typically, electrical conductors are run through a cable that extends along the well to the electrical devices to provide power to the electrical devices from an earth surface location. Signaling (commands and/or data) can also be communicated over the cable between earth surface equipment and downhole electrical devices. In some implementations, electrical conductors are run through a wireline, although in other implementations, electrical conductors can be run through other conveyance structures, such as tubing and so forth.
Well logging applications can involve communication of relatively large amounts of data from a downhole well logging tool to earth surface equipment. A challenge associated with communicating signaling over a transmission line in a well is that the transmission line can be very long (sometimes extending to 30,000 feet or more). Repeaters are generally not allowed in the transmission line that is deployed downhole, which further enhances the challenge of accurately communicating signals from a downhole location over a long-length transmission line to earth surface equipment. Moreover, a further challenge of communicating signaling over a transmission line deployed in a well is that the transmission line and the electrical circuits of the downhole tools are exposed to high temperature (200° C. or more). The above communications challenges faced by a well logging tool can prevent reliable, high bandwidth communication of large amounts of data over the transmission line.
To compensate for high temperatures and long-length transmission lines, it may be desirable to generate relatively high-power signals for transmission over the transmission lines. However, transmitting high-power signals over the transmission lines can result in transmitter distortion, which can impair the ability to detect the signals at receivers and can limit available data rates.